Why I only see the on screen credits?

Unplayable?

If you see the core credits rolling through the screen but cannot play then:

1. If you cannot see the game attract mode behind the credits, then you are missing the game ROMs
2. If you can see the game running but cannot insert coins then you are running a closed version of the core

Cores have three versions:

1. Public version: OSD is gray, you can play with just the core file and compatible ROMs
2. Beta version: OSD is yellow, you will need a valid key file in the right place
3. Private version: OSD is red, these are files for alpha testing and development. They are not meant for final users. If you found one, discard it and get a public/beta one instead

Beta Keys

Although JT cores are available on many FPGA systems, only two of them have a relevant user base and can support all cores: the MiSTer FPGA and the Analog Pocket. These two systems receive beta cores and eventually, public files. In order to distribute beta cores for patrons easily, the binary files are stored in an open location: JTBIN. But, they will require a key to be playable, as described above. Follow these instructions to install your key:

• On MiSTer, copy the file jtbeta.zip from Patreon to the /games/mame folder of your SD card. Do not unzip it. If you have more than one mame folder, MiSTer may fail to find either the jtbeta file or the ROM files. So be careful about that.
• On the Pocket, you will need to unzip the file jtbeta.zip and get the beta.bin from it. Copy beta.bin to each Assets/corename/common folder.

Important

Cores in beta phase are updated each time there is a beta key change. Old beta cores will not work with the new beta file and vice versa. If the beta file changes, make sure you update the cores as well!

The beta key is only changed every 2-3 months, in order to reduce the burden of making manual changes to Patreon supporters.

A public MiSTer core is asking for a beta key!

If you cannot play with a core that is supposed to be public, chances are you have a mix of old and new RBF files (the files that the FPGA load) in your MiSTer _Arcade folder. The easiest way around this is to simply delete the _Arcade folder and run the update script again, so you get a clean and fresh install.

Location of beta.bin on the Analogue Pocket

beta.bin is only required for cores in beta phase but it is easier to just copy it to each Assets/*/common folders. Recently Analogue released a new firmware, version 2.0, that allows to have a single copy of the file in Assets/jtpatreon/common. If your Analogue Pocket is up to date, either the core or the jtpatreon folders will work. If your device is using an old firmware version, you will need to have multiple copies of the file, one per each core.

Again, cores and the beta key file are synchronized. If you mix an old core with a new beta or vice versa, it will not work.

What is that missing ROM id(1) error about?

That is an Analog Pocket message telling you the ROM file is missing. Check out the Pocket installation guide to understand how to generate .rom files.

My Pocket gives me a firmware error

Sometimes you may get an error in the Pocket that is not related to a missing ROM. This normally means that the files in the SD card are not consistent with each other. This may happen if your SD card got data corrupted (like when you pull the card off while the computer is still writing data). Copying the files over again from the PC should fix this.

Sometimes the Pocket may just need a power cycle (turn off and on) in order to read the files properly. Try powering the device off, ejecting the SD card, injecting it, and then booting the system.